The project proposes a study of the effect of hyaluronic acid on inflammatory and degenerative processes of the joint. We propose to determine whether or not hyaluronic acid (HA) in the synovial fluid, in the intercellular matrix of synovial tissue, and in the surface layers of articular cartilage plays a regulatory role in normal and pathological activities of connective tissue cells. It is planned to investigate the transport of hyaluronic acid from the synovial fluid under the three conditions: a) a physiological model; b) an arthritic model; and c) a therapeutic model. We will also investigate what effect increasing the HA concentration of synovial fluid on synovitis and degenerative and regenerative processes in articular cartilage. The effect of corticosteroids on HA transport from the synovial space will also be investigated. The effect of normal and pathological synovial fluid on cells of the lymphomyeloid system will be studied. The metabolism of synovial cells and the effect of HA on their metabolism will be investigated as well as the in vitro enzymatic biosynthesis of HA.